How does the scope of Javascript classes work?

Asked Sep 22 '19 at 10:07

Active Sep 22 '19 at 10:23

Viewed 132 times

I have the following Javascript file:

class Coo {
    constructor() {
    }
}

function foo() {
}

Now if I load this into a browser (with a script tag), there is now a function window.foo defined. However, window.Coo is undefined.

So how does the scope of class work and how is it different from function?

In other words: Where do classes live?

edited Sep 22 '19 at 10:14

asked Sep 22 '19 at 10:07

AndreKR

2

See the linked questions' answers. Global `class` definitions don't add properties to the global object (which is, loosely speaking, `window` on browsers). This is also true of `let` and `const` declarations. They create globals, but not properties on the global object. Older-style declarations (`function`, `var`) at global scope *do* create properties on the global object. When the new forms were being added, TC39 (the steering committee for JS) were trying to reduce the exposure of things. – T.J. Crowder Sep 22 '19 at 10:13

0 Answers0